The Whale and the Hockey Stick

Well, it was certainly born of fire. This is planetary nebula Abell 39, one of the largest spheres in the galaxy… it’s 2.6 light-years across! It really is that color blue. You’re seeing ionized Oxygen gas blown off by the dying star in its center. Look closely for the distant galaxies in the background, including…

Located about 1,300 light-years away, the Iris Nebula is a reflection nebula – unlike most of the nebulas on this site, it’s not made of ionized gases emitting light of their own. It’s just starlight reflecting off clouds of dust. Reflection nebula are harder to image in light-polluted skies, since the narrowband filters we use…

I don’t know why the press has latched onto the name “the green comet” for C/2022 E3 (ZTF) – most comets are green, and it’s too dim to see any color at all if you’re viewing it through binoculars or a telescope. But through 2 hours of total exposure time, the colors do emerge, and…

This morning, my cat woke me up at 3 AM, and I noticed it was clear outside. But, the sun would start rising in just a couple of hours, so doing some super-long-exposure shot of a faint nebula wasn’t in the cards. However, globular clusters don’t take long to image, as they are relatively bright…

A nebula that looks like its name! Formally SH-308, this bubble of gas 60 light-years across is blown out by a hot Wolf-Rayet star at its center. It’s about 4500 light-years away in the constellation Canis Majoris. It’s quite dim, but if you could see it with bionic vision or something, it would be larger…

Hoag’s Object is the weirdest galaxy I know of; it is a “ring galaxy” – a very rare galaxy type that’s just a galactic core of stars, surrounded by a ring of stars that’s seemingly disconnected from its core. This galaxy has always captured my imagination. Just look at this image from the Hubble Space…